The invention concerns a process for manufacturing a flat commutator.
When a commutator is used in an environment that is aggressive for copper, for example, in a fuel containing methanol for motor vehicles, it is customary to designate carbon as the material for the commutator segments. These carbon segments must, however, be supported by segment supporting structures made of copper to be able to connect the coil ends of the rotor coil with the segments without a problem.
A process for manufacturing a carbon flat commutator is already known (DE 40 28 420 A1), which yields a commutator in which all the areas of the existing support body that are made of copper except the connecting hook are completely covered by the carbon segments and the molded plastic material. Therefore this commutator satisfies the highest demands. But its production is relatively expensive.
A known process of the type mentioned at the outset U.S. Pat. No. 5,255,426 is considerably more cost effective; in this process the ring wheel, which is made of carbon, is soldered on the segment supports after forming the hub on the support body, and then both the ring wheel and the support body are segmented by separating cuts. A disadvantage with this commutator is, however, that the cut edges of the support body, i.e., the lateral faces of the copper segment support parts, which border on the air gap, are exposed.
The problem of the invention is, therefore, to designate a process for manufacturing a flat commutator of the type mentioned that yields a commutator that is free of every disadvantage, but can still be designed inexpensively.